Facile Polyolefin Plastics Hydrogenolysis Catalyzed by a Surface Electrophilic d0 Hydride

Polyolefins comprise a major fraction of single-use plastics and yet their catalytic deconstruction/recycling has proven challenging due to their inert hydrocarbon connectivities. Here an electrophilic earth-abundant single-site organozirconium catalyst chemisorbed on a highly Brønsted acidic support and characterized by a broad array of experimental and theoretical techniques, is shown to mediate the rapid hydrogenolytic cleavage of molecular and macromolecular saturated hydrocarbons under mild conditions. For n-hexadecane, hydrogenolysis to light hydrocarbons proceeds with an activity of 690 mol n-hexadecane · mol Zr-1 · h-1 at 150°C/2.5 atm H2 pressure. Under similar solventless conditions, polyethylene, polyethylene-co- 1-octene, isotactic polypropylene, and a post-consumer sandwich bag are rapidly hydrogenolyzed to low molecular mass hydrocarbons via a turnover-limiting C-C scission pathway involving ßalkyl transfer rather than more common σ-bond metathesis.